In hci_abort_conn_sync it is possible that conn is deleted concurrently
by something else, also e.g. when waiting for hdev->lock. This causes
double deletion of the conn, so UAF or conn_hash.list corruption.
Fix by having all code paths check that the connection is still in
conn_hash before deleting it, while holding hdev->lock which prevents
any races.
Log (when powering off while BAP streaming, occurs rarely):
=======================================================================
kernel BUG at lib/list_debug.c:56!
...
? __list_del_entry_valid (lib/list_debug.c:56)
hci_conn_del (net/bluetooth/hci_conn.c:154) bluetooth
hci_abort_conn_sync (net/bluetooth/hci_sync.c:5415) bluetooth
? __pfx_hci_abort_conn_sync+0x10/0x10 [bluetooth]
? lock_release+0x1d5/0x3c0
? hci_disconnect_all_sync.constprop.0+0xb2/0x230 [bluetooth]
? __pfx_lock_release+0x10/0x10
? __kmem_cache_free+0x14d/0x2e0
hci_disconnect_all_sync.constprop.0+0xda/0x230 [bluetooth]
? __pfx_hci_disconnect_all_sync.constprop.0+0x10/0x10 [bluetooth]
? hci_clear_adv_sync+0x14f/0x170 [bluetooth]
? __pfx_set_powered_sync+0x10/0x10 [bluetooth]
hci_set_powered_sync+0x293/0x450 [bluetooth]
=======================================================================
Fixes: 94d9ba9f98 ("Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
a239110ee8